Thanks for all the links, Freedom. His nails aren't too long, and they're not really too short, either. It's just that he digs so hard into everything, literally and figuratively speaking, he ends up exposing the quick. Even when we wait a week before exercising again, he'll still do it. His diet isn't lacking anything that I know of, and one of the suggestions was to give fish oil, which I don't do consistently and will start doing now. I was giving it to him when I remembered, but I will make a point of it, now.

As for the soft claw covers, I thought of that, too, but are they really designed to stay on through extreme play and exercise? I will give them a shot, although his nails aren't so long that they hurt our skin or make clicky sounds on hard floors.

Thanks for the suggestions, we'll keep searching, too!